var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');

var indexRouter = require('./routes/index');
var loginRouter = require('./routes/login');
var studentRouter = require('./routes/student');
var teacherRouter = require('./routes/teacher');
var expertRouter = require('./routes/expert');
var informationRouter = require('./routes/information');

const multerUpload = require('./routes/upload');


var app = express();
var ejs = require('ejs');
app.engine('.html',ejs.__express);
app.set('view engine', 'html');

app.all('*', function(req, res, next) {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "*");
  res.header("Access-Control-Allow-Methods", "PUT,POST,GET,DELETE,OPTIONS");
  res.header("*", ' 3.2.1')
  res.header("Content-Type", "application/json;charset=utf-8");
  if(req.method == 'OPTIONS') {
      //让options请求快速返回
      res.sendStatus(200); 
  } else { 
      next(); 
  }
});
// view engine setup
app.set('views', path.join(__dirname, 'views'));

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', indexRouter);
app.use('/login', loginRouter);
app.use('/student', studentRouter);
app.use('/teacher', teacherRouter);
app.use('/expert', expertRouter);
app.use('/information', informationRouter);
app.use('/upload', multerUpload);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;
